NEW YORK • The United Nations General Assembly has gathered to rethink global strategy in the war on narcotics for the first time in 20 years, citing a global trend towards more liberal drug laws.

During the special session called by Mexico, Guatemala and Colombia, the General Assembly adopted a document that marks a shift away from the "war on drugs" launched in the 1970s, with its approach centred on law enforcement and criminalisation.

"Drug policies that focus on the use of the criminal justice system need to be broadened by embracing a public health approach," said World Health Organisation director Margaret Chan.

A number of Latin American leaders say the war on drugs has failed, having destroyed thousands of lives worldwide. They say there is an irreversible trend towards legalising "soft drugs" such as marijuana.

Last month, reports by medical journal the Lancet and Johns Hopkins University said Portugal and the Czech Republic had shown that decriminalising non-violent drug offences produced compelling health benefits.

"Evidence shows that prohibitionist approaches have not worked: from 1998 to 2008 the number of people using illicit drugs did not change significantly," UN Assistant Secretary-General Magdy Martinez-Soliman wrote in the Guardian newspaper.

Mexican President Enrique Pena Nieto told the gathering his country would soon increase the amount of marijuana allowed for personal use and legalise marijuana for medical purposes. "We should be flexible to change that which has not yielded results," he said.

Colombian President Juan Manuel Santos, also writing in the Guardian, said "the time has come for the world to transit into a different approach in its drug policy". He called for ending the death penalty for drug offences, and non-prison rehabilitation for drug abusers.

However, Indonesia's delegate drew jeers when he declared that the use of the death penalty was a matter for individual states to decide, in a statement backed by Singapore, Saudi Arabia, China, Iran and Pakistan, among other nations.

The document adopted makes no reference to the death penalty, but calls on governments to promote sentencing policies "whereby the severity of penalties is proportionate to the gravity of offences".

AGENCE FRANCE-PRESSE, REUTERS